Vehicle systems may include an engine with an exhaust gas treatment system coupled in its exhaust passage in order to control regulated emissions. In some examples, the exhaust gas treatment system may include a selective catalytic reduction (SCR) system in which an exhaust fluid, such as urea or ammonia, is added to the exhaust stream upstream of a catalyst such that NOx may be reduced by the catalyst. In such an example, the exhaust fluid may be held in an exhaust fluid storage tank which is periodically refilled. In some approaches, the exhaust fluid storage tank may be filled via a dispenser which includes an automatic shut-off of fluid flow such that the exhaust fluid storage tank is not overfilled. For example, a current level of exhaust fluid may be unknown, as a level sensor may only indicate if the exhaust fluid is above or below a threshold level.
The inventors herein have recognized the above issue and have devised an approach to at least partially address it. In one example, a method for a vehicle system includes sensing throughout a range an exhaust fluid level in an exhaust fluid storage tank, and notifying a vehicle operator of a parameter based on the sensed exhaust fluid level.
By sensing the exhaust fluid level throughout a range, such as from a near empty exhaust fluid level to a near full exhaust fluid level, various information regarding the exhaust fluid storage tank may be determined. For example, the parameter which is determined may be an exhaust fluid consumption rate or an amount of exhaust fluid to be added to the exhaust fluid storage tank. Further, the operator of the vehicle may be notified of the parameter via a display such that appropriate action may be taken. For example, when the amount of exhaust fluid to be added to the exhaust fluid storage tank is displayed on a dashboard of the vehicle, the operator may add an amount of exhaust fluid to the exhaust fluid storage tank such that the exhaust fluid storage tank is filled to a maximum level without overfilling the exhaust fluid storage tank. In one example, the exhaust fluid may be added to the exhaust fluid storage tank from a vessel such as a bottle without an automatic fluid flow shut-off. In such an example, the vehicle operator may pour a quantity of exhaust fluid into the exhaust fluid storage tank based on the sensed exhaust fluid level with a reduced possibility of overfilling the exhaust fluid storage tank.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.